[PATCH v2] dt-bindings: iio: adc: stm32-adc: convert bindings to json-schema
From: Fabrice Gasnier
Date: Fri Dec 06 2019 - 11:19:39 EST
Convert the STM32 ADC binding to DT schema format using json-schema
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx>
---
Note: this applies on top of IIO tree currently (iio-for-5.5c).
Changes in V2:
- Take almost all of Rob suggestions (removed reg generic description,
added minItems, maxItems, st,max-clk-rate-hz range, drop some pipes,
simplify clock-names, remove unneeded allOfs)
- For now, keep all in one file despite there are lots of if/thens in the
bindings
---
.../devicetree/bindings/iio/adc/st,stm32-adc.txt | 149 -------
.../devicetree/bindings/iio/adc/st,stm32-adc.yaml | 454 +++++++++++++++++++++
2 files changed, 454 insertions(+), 149 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
create mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
deleted file mode 100644
index 8de9331..00000000
--- a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
+++ /dev/null
@@ -1,149 +0,0 @@
-STMicroelectronics STM32 ADC device driver
-
-STM32 ADC is a successive approximation analog-to-digital converter.
-It has several multiplexed input channels. Conversions can be performed
-in single, continuous, scan or discontinuous mode. Result of the ADC is
-stored in a left-aligned or right-aligned 32-bit data register.
-Conversions can be launched in software or using hardware triggers.
-
-The analog watchdog feature allows the application to detect if the input
-voltage goes beyond the user-defined, higher or lower thresholds.
-
-Each STM32 ADC block can have up to 3 ADC instances.
-
-Each instance supports two contexts to manage conversions, each one has its
-own configurable sequence and trigger:
-- regular conversion can be done in sequence, running in background
-- injected conversions have higher priority, and so have the ability to
- interrupt regular conversion sequence (either triggered in SW or HW).
- Regular sequence is resumed, in case it has been interrupted.
-
-Contents of a stm32 adc root node:
------------------------------------
-Required properties:
-- compatible: Should be one of:
- "st,stm32f4-adc-core"
- "st,stm32h7-adc-core"
- "st,stm32mp1-adc-core"
-- reg: Offset and length of the ADC block register set.
-- interrupts: One or more interrupts for ADC block. Some parts like stm32f4
- and stm32h7 share a common ADC interrupt line. stm32mp1 has two separate
- interrupt lines, one for each ADC within ADC block.
-- clocks: Core can use up to two clocks, depending on part used:
- - "adc" clock: for the analog circuitry, common to all ADCs.
- It's required on stm32f4.
- It's optional on stm32h7.
- - "bus" clock: for registers access, common to all ADCs.
- It's not present on stm32f4.
- It's required on stm32h7.
-- clock-names: Must be "adc" and/or "bus" depending on part used.
-- interrupt-controller: Identifies the controller node as interrupt-parent
-- vdda-supply: Phandle to the vdda input analog voltage.
-- vref-supply: Phandle to the vref input analog reference voltage.
-- #interrupt-cells = <1>;
-- #address-cells = <1>;
-- #size-cells = <0>;
-
-Optional properties:
-- A pinctrl state named "default" for each ADC channel may be defined to set
- inX ADC pins in mode of operation for analog input on external pin.
-- booster-supply: Phandle to the embedded booster regulator that can be used
- to supply ADC analog input switches on stm32h7 and stm32mp1.
-- vdd-supply: Phandle to the vdd input voltage. It can be used to supply ADC
- analog input switches on stm32mp1.
-- st,syscfg: Phandle to system configuration controller. It can be used to
- control the analog circuitry on stm32mp1.
-- st,max-clk-rate-hz: Allow to specify desired max clock rate used by analog
- circuitry.
-
-Contents of a stm32 adc child node:
------------------------------------
-An ADC block node should contain at least one subnode, representing an
-ADC instance available on the machine.
-
-Required properties:
-- compatible: Should be one of:
- "st,stm32f4-adc"
- "st,stm32h7-adc"
- "st,stm32mp1-adc"
-- reg: Offset of ADC instance in ADC block (e.g. may be 0x0, 0x100, 0x200).
-- clocks: Input clock private to this ADC instance. It's required only on
- stm32f4, that has per instance clock input for registers access.
-- interrupts: IRQ Line for the ADC (e.g. may be 0 for adc@0, 1 for adc@100 or
- 2 for adc@200).
-- st,adc-channels: List of single-ended channels muxed for this ADC.
- It can have up to 16 channels on stm32f4 or 20 channels on stm32h7, numbered
- from 0 to 15 or 19 (resp. for in0..in15 or in0..in19).
-- st,adc-diff-channels: List of differential channels muxed for this ADC.
- Depending on part used, some channels can be configured as differential
- instead of single-ended (e.g. stm32h7). List here positive and negative
- inputs pairs as <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered
- from 0 to 19 on stm32h7)
- Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is required.
- Both properties can be used together. Some channels can be used as
- single-ended and some other ones as differential (mixed). But channels
- can't be configured both as single-ended and differential (invalid).
-- #io-channel-cells = <1>: See the IIO bindings section "IIO consumers" in
- Documentation/devicetree/bindings/iio/iio-bindings.txt
-
-Optional properties:
-- dmas: Phandle to dma channel for this ADC instance.
- See ../../dma/dma.txt for details.
-- dma-names: Must be "rx" when dmas property is being used.
-- assigned-resolution-bits: Resolution (bits) to use for conversions. Must
- match device available resolutions:
- * can be 6, 8, 10 or 12 on stm32f4
- * can be 8, 10, 12, 14 or 16 on stm32h7
- Default is maximum resolution if unset.
-- st,min-sample-time-nsecs: Minimum sampling time in nanoseconds.
- Depending on hardware (board) e.g. high/low analog input source impedance,
- fine tune of ADC sampling time may be recommended.
- This can be either one value or an array that matches 'st,adc-channels' list,
- to set sample time resp. for all channels, or independently for each channel.
-
-Example:
- adc: adc@40012000 {
- compatible = "st,stm32f4-adc-core";
- reg = <0x40012000 0x400>;
- interrupts = <18>;
- clocks = <&rcc 0 168>;
- clock-names = "adc";
- vref-supply = <®_vref>;
- interrupt-controller;
- pinctrl-names = "default";
- pinctrl-0 = <&adc3_in8_pin>;
-
- #interrupt-cells = <1>;
- #address-cells = <1>;
- #size-cells = <0>;
-
- adc@0 {
- compatible = "st,stm32f4-adc";
- #io-channel-cells = <1>;
- reg = <0x0>;
- clocks = <&rcc 0 168>;
- interrupt-parent = <&adc>;
- interrupts = <0>;
- st,adc-channels = <8>;
- dmas = <&dma2 0 0 0x400 0x0>;
- dma-names = "rx";
- assigned-resolution-bits = <8>;
- };
- ...
- other adc child nodes follow...
- };
-
-Example to setup:
-- channel 1 as single-ended
-- channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
-
- adc: adc@40022000 {
- compatible = "st,stm32h7-adc-core";
- ...
- adc1: adc@0 {
- compatible = "st,stm32h7-adc";
- ...
- st,adc-channels = <1>;
- st,adc-diff-channels = <2 6>, <3 7>;
- };
- };
diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
new file mode 100644
index 00000000..60a0212
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
@@ -0,0 +1,454 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/bindings/iio/adc/st,stm32-adc.yaml#";
+$schema: "http://devicetree.org/meta-schemas/core.yaml#";
+
+title: STMicroelectronics STM32 ADC bindings
+
+description: |
+ STM32 ADC is a successive approximation analog-to-digital converter.
+ It has several multiplexed input channels. Conversions can be performed
+ in single, continuous, scan or discontinuous mode. Result of the ADC is
+ stored in a left-aligned or right-aligned 32-bit data register.
+ Conversions can be launched in software or using hardware triggers.
+
+ The analog watchdog feature allows the application to detect if the input
+ voltage goes beyond the user-defined, higher or lower thresholds.
+
+ Each STM32 ADC block can have up to 3 ADC instances.
+
+maintainers:
+ - Fabrice Gasnier <fabrice.gasnier@xxxxxx>
+
+properties:
+ compatible:
+ enum:
+ - st,stm32f4-adc-core
+ - st,stm32h7-adc-core
+ - st,stm32mp1-adc-core
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ description: |
+ One or more interrupts for ADC block, depending on part used:
+ - stm32f4 and stm32h7 share a common ADC interrupt line.
+ - stm32mp1 has two separate interrupt lines, one for each ADC within
+ ADC block.
+ minItems: 1
+ maxItems: 2
+
+ clocks:
+ description: |
+ Core can use up to two clocks, depending on part used:
+ - "adc" clock: for the analog circuitry, common to all ADCs.
+ It's required on stm32f4.
+ It's optional on stm32h7 and stm32mp1.
+ - "bus" clock: for registers access, common to all ADCs.
+ It's not present on stm32f4.
+ It's required on stm32h7 and stm32mp1.
+
+ clock-names: true
+
+ st,max-clk-rate-hz:
+ description:
+ Allow to specify desired max clock rate used by analog circuitry.
+
+ vdda-supply:
+ description: Phandle to the vdda input analog voltage.
+
+ vref-supply:
+ description: Phandle to the vref input analog reference voltage.
+
+ booster-supply:
+ description:
+ Phandle to the embedded booster regulator that can be used to supply ADC
+ analog input switches on stm32h7 and stm32mp1.
+
+ vdd-supply:
+ description:
+ Phandle to the vdd input voltage. It can be used to supply ADC analog
+ input switches on stm32mp1.
+
+ st,syscfg:
+ description:
+ Phandle to system configuration controller. It can be used to control the
+ analog circuitry on stm32mp1.
+ allOf:
+ - $ref: "/schemas/types.yaml#/definitions/phandle-array"
+
+ interrupt-controller: true
+
+ '#interrupt-cells':
+ const: 1
+
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 0
+
+allOf:
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: st,stm32f4-adc-core
+
+ then:
+ properties:
+ clocks:
+ maxItems: 1
+
+ clock-names:
+ const: adc
+
+ interrupts:
+ items:
+ - description: interrupt line common for all ADCs
+
+ st,max-clk-rate-hz:
+ minimum: 600000
+ maximum: 36000000
+ default: 36000000
+
+ booster-supply: false
+
+ vdd-supply: false
+
+ st,syscfg: false
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: st,stm32h7-adc-core
+
+ then:
+ properties:
+ clocks:
+ minItems: 1
+ maxItems: 2
+
+ clock-names:
+ items:
+ - const: bus
+ - const: adc
+ minItems: 1
+ maxItems: 2
+
+ interrupts:
+ items:
+ - description: interrupt line common for all ADCs
+
+ st,max-clk-rate-hz:
+ minimum: 120000
+ maximum: 36000000
+ default: 36000000
+
+ vdd-supply: false
+
+ st,syscfg: false
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: st,stm32mp1-adc-core
+
+ then:
+ properties:
+ clocks:
+ minItems: 1
+ maxItems: 2
+
+ clock-names:
+ items:
+ - const: bus
+ - const: adc
+ minItems: 1
+ maxItems: 2
+
+ interrupts:
+ items:
+ - description: interrupt line for ADC1
+ - description: interrupt line for ADC2
+
+ st,max-clk-rate-hz:
+ minimum: 120000
+ maximum: 36000000
+ default: 36000000
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - clocks
+ - clock-names
+ - vdda-supply
+ - vref-supply
+ - interrupt-controller
+ - '#interrupt-cells'
+ - '#address-cells'
+ - '#size-cells'
+
+patternProperties:
+ "^adc@[0-9]+$":
+ type: object
+ description:
+ An ADC block node should contain at least one subnode, representing an
+ ADC instance available on the machine.
+
+ properties:
+ compatible:
+ enum:
+ - st,stm32f4-adc
+ - st,stm32h7-adc
+ - st,stm32mp1-adc
+
+ reg:
+ description: |
+ Offset of ADC instance in ADC block. Valid values are:
+ - 0x0: ADC1
+ - 0x100: ADC2
+ - 0x200: ADC3 (stm32f4 only)
+ maxItems: 1
+
+ '#io-channel-cells':
+ const: 1
+
+ interrupts:
+ description: |
+ IRQ Line for the ADC instance. Valid values are:
+ - 0 for adc@0
+ - 1 for adc@100
+ - 2 for adc@200 (stm32f4 only)
+ maxItems: 1
+
+ clocks:
+ description:
+ Input clock private to this ADC instance. It's required only on
+ stm32f4, that has per instance clock input for registers access.
+ maxItems: 1
+
+ dmas:
+ description: RX DMA Channel
+ maxItems: 1
+
+ dma-names:
+ const: rx
+
+ assigned-resolution-bits:
+ description: |
+ Resolution (bits) to use for conversions:
+ - can be 6, 8, 10 or 12 on stm32f4
+ - can be 8, 10, 12, 14 or 16 on stm32h7 and stm32mp1
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+
+ st,adc-channels:
+ description: |
+ List of single-ended channels muxed for this ADC. It can have up to:
+ - 16 channels, numbered from 0 to 15 (for in0..in15) on stm32f4
+ - 20 channels, numbered from 0 to 19 (for in0..in19) on stm32h7 and
+ stm32mp1.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+
+ st,adc-diff-channels:
+ description: |
+ List of differential channels muxed for this ADC. Some channels can
+ be configured as differential instead of single-ended on stm32h7 and
+ on stm32mp1. Positive and negative inputs pairs are listed:
+ <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered from 0 to 19.
+
+ Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is
+ required. Both properties can be used together. Some channels can be
+ used as single-ended and some other ones as differential (mixed). But
+ channels can't be configured both as single-ended and differential.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-matrix
+ - items:
+ items:
+ - description: |
+ "vinp" indicates positive input number
+ minimum: 0
+ maximum: 19
+ - description: |
+ "vinn" indicates negative input number
+ minimum: 0
+ maximum: 19
+
+ st,min-sample-time-nsecs:
+ description:
+ Minimum sampling time in nanoseconds. Depending on hardware (board)
+ e.g. high/low analog input source impedance, fine tune of ADC
+ sampling time may be recommended. This can be either one value or an
+ array that matches "st,adc-channels" and/or "st,adc-diff-channels"
+ list, to set sample time resp. for all channels, or independently for
+ each channel.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32-array
+
+ allOf:
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: st,stm32f4-adc
+
+ then:
+ properties:
+ reg:
+ enum:
+ - 0x0
+ - 0x100
+ - 0x200
+
+ interrupts:
+ minimum: 0
+ maximum: 2
+
+ assigned-resolution-bits:
+ enum: [6, 8, 10, 12]
+ default: 12
+
+ st,adc-channels:
+ minItems: 1
+ maxItems: 16
+ minimum: 0
+ maximum: 15
+
+ st,adc-diff-channels: false
+
+ st,min-sample-time-nsecs:
+ minItems: 1
+ maxItems: 16
+ minimum: 80
+
+ required:
+ - clocks
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - st,stm32h7-adc
+ - st,stm32mp1-adc
+
+ then:
+ properties:
+ reg:
+ enum:
+ - 0x0
+ - 0x100
+
+ interrupts:
+ minimum: 0
+ maximum: 1
+
+ assigned-resolution-bits:
+ enum: [8, 10, 12, 14, 16]
+ default: 16
+
+ st,adc-channels:
+ minItems: 1
+ maxItems: 20
+ minimum: 0
+ maximum: 19
+
+ st,min-sample-time-nsecs:
+ minItems: 1
+ maxItems: 20
+ minimum: 40
+
+ additionalProperties: false
+
+ anyOf:
+ - required:
+ - st,adc-channels
+ - required:
+ - st,adc-diff-channels
+
+ required:
+ - compatible
+ - reg
+ - interrupts
+ - '#io-channel-cells'
+
+examples:
+ - |
+ // Example 1: with stm32f429
+ adc123: adc@40012000 {
+ compatible = "st,stm32f4-adc-core";
+ reg = <0x40012000 0x400>;
+ interrupts = <18>;
+ clocks = <&rcc 0 168>;
+ clock-names = "adc";
+ st,max-clk-rate-hz = <36000000>;
+ vdda-supply = <&vdda>;
+ vref-supply = <&vref>;
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ adc@0 {
+ compatible = "st,stm32f4-adc";
+ #io-channel-cells = <1>;
+ reg = <0x0>;
+ clocks = <&rcc 0 168>;
+ interrupt-parent = <&adc123>;
+ interrupts = <0>;
+ st,adc-channels = <8>;
+ dmas = <&dma2 0 0 0x400 0x0>;
+ dma-names = "rx";
+ assigned-resolution-bits = <8>;
+ };
+ // ...
+ // other adc child nodes follow...
+ };
+
+ - |
+ // Example 2: with stm32mp157c to setup ADC1 with:
+ // - channel 1 as single-ended
+ // - channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/clock/stm32mp1-clks.h>
+ adc12: adc@48003000 {
+ compatible = "st,stm32mp1-adc-core";
+ reg = <0x48003000 0x400>;
+ interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 90 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&rcc ADC12>, <&rcc ADC12_K>;
+ clock-names = "bus", "adc";
+ booster-supply = <&booster>;
+ vdd-supply = <&vdd>;
+ vdda-supply = <&vdda>;
+ vref-supply = <&vref>;
+ st,syscfg = <&syscfg>;
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ adc@0 {
+ compatible = "st,stm32mp1-adc";
+ #io-channel-cells = <1>;
+ reg = <0x0>;
+ interrupt-parent = <&adc12>;
+ interrupts = <0>;
+ st,adc-channels = <1>;
+ st,adc-diff-channels = <2 6>, <3 7>;
+ st,min-sample-time-nsecs = <5000>;
+ dmas = <&dmamux1 9 0x400 0x05>;
+ dma-names = "rx";
+ };
+ // ...
+ // other adc child node follow...
+ };
+
+...
--
2.7.4